Angle-Independent Anisotropic Filtering At Last

For a number of years now the quality of anisotropic filtering has been slowly improving. Early implementations from AMD and NVIDIA were highly angle-dependent, resulting in a limited improvement to image quality from such filtering. The angle-dependent nature lead to shimmering and other artifacting that was not ideal.

As of the previous generation of cards, the quality of anisotropic filtering had become pretty good. NVIDIA’s best filtering mode was pretty close to angle-independent, and AMD’s only slightly worse. Neither was perfect, but neither was bad either.


The Radeon HD 4890


The GeForce GTX 285

However so long as no one had an angle-independent implementation, there was room to improve. And AMD has gone there. The anisotropic filtering algorithm used by the 5000 series is now truly and completely angle-independent. There are no more filtering tricks being used.


The Radeon HD 5870: Perfection

As you can see, the MIP maps in our venerable D3D AF Tester are perfectly circular, the hallmark of an angle-independent implementation. With angle-independent filtering, this effectively marks the end of the filtering arms race. AMD has won, and should NVIDIA catch up in the future the two would merely be tied. There’s nowhere left to go for quality beyond angle-independent filtering at the moment.

AMD tells us that there is no performance hit with their new algorithm compared to their old one. This is a bit hard to test since we can’t enable the old algorithm on the 5870, but certainly whatever performance hit there is, is similarly minor. In all of the testing we’re doing today, you will see results done with 16x anisotropic filtering used.

What you won’t see however is a difference, particularly with our static screenshots. When discussing the matter, AMD noted that the difference in perceived quality between the old algorithm and the new one was practically the same. After looking at matters we find ourselves in agreement with AMD; we were not able to come up with any situations where there was a noticeable difference, beyond the obvious AF quality tests that are designed to identify such changes.

Regardless of the outcome, AMD deserves kudos for making angle-independent anisotropic filtering happen. It’s demonstrably perfect filtering with no speed hit versus the previous generation of filtering; making it in essence a “free” improvement in image quality, however slight the real-world results are. We’re always ready to get better image quality out of our video cards, after all.

More GDDR5 Technologies: Memory Error Detection & Temperature Compensation The Return of Supersample AA
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  • RubberJohnny - Thursday, September 24, 2009 - link

    Well silicondoc you sure have some hatred for ATI/love for nvidia.

    It's almost as if you work for the green team...

    You seem to have all this time on your hands to go around the net looking for links to spread FUD...sitting on new egg watching these cards come in and out of stock like you have a vested interest in seeing ATI fail...unlike any sane person it appears you want nvidia to have a monopoly on the industry?

    Maybe you are privy to some inside info over at nvidia and know they have nothing to counter the 5870 with?

    Maybe the cash they paid you to spin these BS comments would have been better spent on R&D?
  • SiliconDoc - Thursday, September 24, 2009 - link

    That's a nice personal, grating, insulting ripppp, it's almost funny, too.
    ---
    The real problems remain.
    I bring up this stuff because of course, no one else will, it is almost forbidden. Telling the truth shouldn't be that hard, and calling it fairly and honestly should not be such a burden.
    I will gladly take correction when one of you noticing insulters has any to offer. Of course, that never comes.
    Break some new ground, won't you ?
    I don't think you will, nor do I think anyone else will - once again, that simply confirms my factual points.
    I guess I'll give you a point for complaining about delivery, if that's what you were doing, but frankly, there are a lot of complainers here no different - let's take for instance the ATI Radeon HD 4890 vs. NVIDIA GeForce GTX 275 article here.
    http://www.anandtech.com/video/showdoc.aspx?i=3539">http://www.anandtech.com/video/showdoc.aspx?i=3539
    Boy, the red fans went into rip mode, and Anand came in and changed the articles (Derek's) words and hence "result", from GTX275 wins to ATI4890 wins.
    --
    No, it's not just me, it's just the bias here consistently leans to ati, and wether it's rooting for the underdog that causes it, or the brooding undercurrent hatred that surfaces for "the bigshot" "greedy" "ripoff artist" "nvidia overchargers" "industry controlling and bribing" "profit demon" Nvidia, who knows...
    I'm just not afraid to point it out, since it's so sickening, yes, probably just to me, "I'm sure".
    How about this glaring one I have never pointed out even to this day, but will now:
    ATI is ALWAYS listed first, or "on top" - and of course, NVIDIA, second, and it is no doubt, in the "reviewer's minds" because of "the alphabet", and "here we go in alphabetical order".
    A very, very convenient excuse, that quite easily causes a perception bias, that is quite marked for the readers.
    But, that's ok.
    ---
    So, you want to tell me why I shouldn't laugh out loud when ATI uses NVIDIA cards to develope their "PhysX" competition Bullet ?
    ROFLMAO
    I have heard 100 times here (from guess whom) that the ati has the wanted "new technology", so will that same refrain come when NVIDIA introduces their never before done MIMD capable cores in a few months ? LOL
    I can hardly wait to see the "new technology" wannabes proclaiming their switched fealty.
    Gee sorry for noticing such things, I guess I should be a mind numbed zombie babbling along with the PC required fanning for ati ?
  • silverblue - Thursday, September 24, 2009 - link

    No; if he did work for nVidia, he'd be far better informed and far less prone to using the phrase "red rooster" every five seconds.
  • crackshot91 - Wednesday, September 23, 2009 - link

    Any possibility of benchmarks with a core 2 duo?

    I wanna know if it will be necessary to upgrade to an i5 or i7 (All new mobo) to see big performance gains over my 8800GT. Will a C2D E6750 @ 3.2GHz bottleneck it?
  • Ryan Smith - Wednesday, September 23, 2009 - link

    Our recent Core i7 860 article should do an adequate job of answering that question. Several of the benchmarks were taken right out of this article.
  • therealnickdanger - Wednesday, September 23, 2009 - link

    You dedicated a full page to the flawless performance of its A/V output, but didn't mention it in the "features" part of the conclusion. It's a very powerful feature, IMO. Granted, this card may be a tad too hot and loud to find a home in a lot of HTPCs, but it's still an awesome feature and you should probably append your conclusion... just a suggestion though.

    Ultimately, I have to admit to being a little disappointed by the performance of this card. All the Eyefinity hype and playable framerates at massive 7000x3000 resolutions led me to believe that this single card would scale down and simply dominate everything at the 30" level and below. It just seems logical, so I was taken aback when it was beat by, well, anything else. I expected the 5870 and 5870CF to be at the top of every chart. Oh well.

    Awesome article though! I'm sure there's a 5850 in my future!
  • MrMom - Wednesday, September 23, 2009 - link

    Does anyone have a good explanation why the massive HD5870 is still slower/@par with the GTX295?

    Thanks
  • SiliconDoc - Thursday, September 24, 2009 - link

    Yes, because the ati core "really sucks". It needs DDR5, and much higher MHZ to compete with Nvidia, and their what, over 1 year old core. LOL Even their own 4870x2.
    Or the 3 year old G92 vs the ddr3 "4850" the "topcore" before yesterday. (the ati topcore minus the well done 3m mhz+ REBRAND ring around the 4890)
    That's the sad, actual truth. That's the truth many cannot bear to bring themselves to realize, and it's going to get WORSE for them very soon, with nvidia's next release, with ddr5, a 512 bit bus, and the NEW TECHNOLOGY BY NVIDIA THAT ATI DOES NOT HAVE MIMD capable cores.
    Oh, I can hardly wait, but you bet I'm going to wait, you can count on that 100%.

  • Spoelie - Thursday, September 24, 2009 - link

    because those are 2 480mm² dies, while this is only 1 360mm² die?
  • Griswold - Wednesday, September 23, 2009 - link

    Its one GPU instead of two, maybe?

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